Python provides several built-in data structures to store collections of data. The most commonly used are Lists, Tuples, and Sets. Each has unique features and use cases.

1. Lists in Python

A list is an ordered, mutable (changeable) collection of items. Lists can hold elements of different data types.

Creating a List


fruits = ["apple", "banana", "cherry"]
print(fruits)  # ['apple', 'banana', 'cherry']


Accessing Elements


print(fruits[0])   # apple
print(fruits[-1])  # cherry


Modifying Lists


fruits[1] = "mango"
print(fruits)  # ['apple', 'mango', 'cherry']


List Methods

* `append()` – Add element at the end
* `insert()` – Insert at specific index
* `remove()` – Remove by value
* `pop()` – Remove by index
* `sort()` – Sort the list
* `reverse()` – Reverse the list

Example:


numbers = [3, 1, 4, 2]
numbers.sort()
print(numbers)  # [1, 2, 3, 4] 

  2. Tuples in Python

A tuple is an ordered, immutable collection of elements. Once created, you cannot modify a tuple.

Creating a Tuple


dimensions = (1920, 1080)
print(dimensions)  # (1920, 1080)


Accessing Elements


print(dimensions[0])  # 1920


Why Use Tuples?

* They are faster than lists
* Useful for fixed data (e.g., coordinates)

Tuple Methods

* `count()` – Count occurrences
* `index()` – Find index of an element

Example:


colors = ("red", "blue", "red")
print(colors.count("red"))  # 2


  3. Sets in Python

A set is an unordered collection of unique elements.

* No duplicate values
* No indexing or slicing

Creating a Set


colors = {"red", "green", "blue"}
print(colors)  # {'blue', 'green', 'red'}


Adding and Removing Elements


colors.add("yellow")
colors.remove("red")
print(colors)  # {'blue', 'green', 'yellow'}


Set Operations

* `union()` → Combines elements from both sets
* `intersection()` → Common elements
* `difference()` → Elements present in one set but not the other

Example:


a = {1, 2, 3}
b = {3, 4, 5}
print(a.union(b))         # {1, 2, 3, 4, 5}
print(a.intersection(b))  # {3}


 

 Summary

* Lists – Ordered, mutable, allows duplicates
* Tuples – Ordered, immutable, allows duplicates
* Sets – Unordered, mutable, no duplicates